UPS

I'm planning to buy a UPS for my system and would prefer to have it supply the humidifier also. I thought I read that the humidifiers won't work on anything other than sine wave power.

Most of the candidate UPS models I'm looking at are described as having a "Stepped approximation to a sinewave." Should I assume those will not work? What is it about humidifiers that require pure sine waves?

KSMike wrote:What is it about humidifiers that require pure sine waves?

Many humdifiers use thyristor devices in a phase control approach to adjust the power applied to the heating element, in order to set the temperature on the heating plate. This requires a true sine wave input signal to get adequate "granularity" in the level of adjustment.

The "modified sine waves" (which are generally just square waves with the edges rounded off in reality) which are produced by lower cost UPS's, and inverters, are not amenible to phase control approaches, and can burn out the control devices.

See http://en.wikipedia.org/wiki/Phase_fired_controllers

Cheers,

Bill

You can avoid all that trouble if you just get the 12V M series humidifier and use battery power for both.

Thanks!

Bill, I should've figured out that a thyristor was used for temp. control. That makes sense and explains why these humidifiers, which seem to work very well for the most part, are relatively inexpensive.

A plain old battery would indeed solve the problem, but I'd prefer to have a sealed, replaceable (relatively inexpensively) battery that doesn't have to have a separate charger, etc. I guess I need to decide whether it's worth the trouble to protect the humidifier.

At over a grand for one with pure sine I'll use a ups with the less than pure but still better than what my local grid puts out. If the humidifier burns out I'll get a F&p replacement for 150.00 or so

If you can sleep thru the alarms generated when a UPS is in use you are truely sleep deprived to the Max.

I didn't realize until just now that there's a sealed Respironics pack that comes with it's own charger, pouch, etc. At $300 for a set of parts that I know only cost around $100 to put together, it's grossly overpriced. However, it's a nice complete package with all cables, etc., and has good reviews - so maybe that's the way to go. The humidifier still can't be used with it, but I guess that's just a problem with no solution.

I did wonder about the alarms on a UPS and thought it would be necessary to have the ability to turn them all off. I'm not sure there is such a thing.

It says in the Respironics M-Series Humidifier Manual:

This humidifier is suitable for use with typical DC-to-AC inverters and UPSs (uninterruptible power supplies). (200 watts at 120 V and 400 watts at 220 V)

The Dreamer.

Thanks, Dreamer. Just noticed you're out in Manhattan. I hope the weather didn't get too nasty out there tonight.

I'm surprised how much power the M Series humidifier uses. The F&P 150 is rated for 94W. I wonder why the M-Series humidifier is considered suitable for UPS when others aren't? Pricing on them is about the same, so I would imagine they use the same types and classes of electronics.

The most likely season for power failures here is spring & summer, and the ambient air is probably humid enough at those times to get by without the humidifier (or use passover). It's much less likely that we'd have an outage during the winter, but if we ever did I'd be in big trouble without the humidifier.

KSMike wrote:I didn't realize until just now that there's a sealed Respironics pack that comes with it's own charger, pouch, etc. At $300 for a set of parts that I know only cost around $100 to put together, it's grossly overpriced. However, it's a nice complete package with all cables, etc., and has good reviews - so maybe that's the way to go. The humidifier still can't be used with it, but I guess that's just a problem with no solution.

I did wonder about the alarms on a UPS and thought it would be necessary to have the ability to turn them all off. I'm not sure there is such a thing.

YOu can turn the alarm off on most UPS units...I have them off on all of ours here at the house, EXCEPT the one the CPAPs are on....I WANT that alarm, it's why I bought them...the machines will stay on long enough for us to wake up. If the power stays out hubby can start the generator....

Ya, it was pretty rumbly last night. But, I hadn't gone to bed yet....the neighbors were louder....it was fake patty's day.

Unfortunately I own a number of UPSs that can't be silenced. And, some of the newer ones I got...require a Windows computer to silence them. OTOH, the one I have in the bedroom is supposed to be pretty quiet....only beep once when the power fails and then quiet until there's only 10 minutes left.

Haven't had an outage since starting CPAP, but in the past...before UPSs, it was the deafening silence that woke me up and prevented me from sleeping (the silence makes me hear all the other stuff that I don't want to hear, like the building creaking in the wind.) Now there's the incessant beeping of the UPSs in other rooms. Also I have neighbors that feel compelled to howl like animals when the power goes out at night.... college kids these days....

Actually, I experienced deafening silence during the Xmas break. It get's really quiet in the building with almost everybody gone. And, the neighbor upstairs had moved out....so I got to listen to the building make lots of strange sounds when it was really windy. Almost didn't get the sound machine, I had hoped that it would cover up the rhythmically squeaking bed springs of the neighbor upstairs. But, now I've been trying it for other things (finally got it loud enough to mask the CPAP machine, and found that it was loud enough to keep me up at night...)

The Dreamer.

Ugh. Apartment life. When I lived in an apartment in college we didn't have too many noisy neighbors. We only had roaches - or are they "water bugs" lol - that were the size of my hands.

I dunno, I'm going back and forth on this. The battery pack would be great for traveling, camping (I've been concerned about how I'm going to make that work), etc., but I still like the idea of having an automatically switched power supply during an outage. Something tells me I'm going to end up with both.

Does the constant spending of money ever slow down with cpap hardware?

TheDreamer wrote:It says in the Respironics M-Series Humidifier Manual:

This humidifier is suitable for use with typical DC-to-AC inverters and UPSs (uninterruptible power supplies). (200 watts at 120 V and 400 watts at 220 V)

The Dreamer.

Their info doesn't make any sense. if something on A/C draws draws 200 watts, the same load (WORK) would use 100 watts at 220. Them's the rules. Now if you ran a 110 volt unit on 220 volts, then it would draw more power and you would need a fire hose.

Does the constant spending of money ever slow down with cpap hardware? Yes, when we get smarter, or run out of money. Jim

TheDreamer wrote:It says in the Respironics M-Series Humidifier Manual:

This humidifier is suitable for use with typical DC-to-AC inverters and UPSs (uninterruptible power supplies). (200 watts at 120 V and 400 watts at 220 V)

The Dreamer.

Sweet.

Wow, reading the documentation. What a concept!!!

My little idea of getting an old UPS and using it as a power alarm went the way that anyone with a little forethought might have predicted. The batteries in all of my units were long gone. So I'll just buy a cheapy...

Goofproof wrote:Their info doesn't make any sense. if something on A/C draws draws 200 watts, the same load (WORK) would use 100 watts at 220. Them's the rules. Now if you ran a 110 volt unit on 220 volts, then it would draw more power and you would need a fire hose.

Does the constant spending of money ever slow down with cpap hardware? Yes, when we get smarter, or run out of money. Jim

Not quite. If the power supply can use anything from 110 to 240 (which is pretty standard these days) it'll use 100W not matter what the voltage. I think you're confusing watts with amps.